Exploring Science: Living Things and Chemistry Basics

1. Chapter 1 and Chapter 2 Introduction to Science and basic chemistry

2. INTRODUCTION

3. 3 Main groups of living things 1. Eukarya • More complicated than the last two groups • Animals and plants are examples of this group 2. Bacteria- some can make you sick 3. Archaea- similar to bacteria, harmless

4. 4 KINGDOMS of Eukarya • These are the 4 subgroups of Eukarya ANIMALS- HUMANS, FLIES PLANTS- TREES, FLOWERS FUNGI- MILDEW AND MOLD PROTISTA- POND SCUM, AMOEBA

5. STEPS OF THE SCIENTIFIC METHOD • ACCUMULATE DATA- collect info. • FORM A HYPOTHESIS- A TESTABLE STATEMENT, AN EDUCATED GUESS • EXPERIMENT AND OBSERVE • COLLECT NEW DATA • FORM A CONCLUSION and RETEST if hypothesis is incorrect

6. PROPER EXPERIMENTS • HAVE A CONTROL (PLACEBO) • CONTROL- ELIMINATES VARIABLES • New medications are tested by giving some volunteers a placebo (sugar pill). The volunteers think they are getting the real medication. The volunteers are asked how they feel after taking the placebo and these results are compared to those of the people that are taking the actual medication

7. Basics of Chemistry THE CHEMISTRY OF LIFE

8. ELEMENTS • BASIC SUBSTANCES THAT CANNOT BE BROKEN DOWN FURTHER INTO SIMPLER SUBSTANCES • 92 NATURALLY OCCURRING • 90% OF THE BODY IS COMPOSED OF THE ELEMENTS CARBON, OXYGEN AND HYDROGEN

9. ATOM • THE SMALLEST WHOLE UNIT OF AN ELEMENT • ATOMS HAVE 3 PARTICLES • NUCLEUS- WITH PROTONS (+) AND NEUTRONS (NO CHARGE) • ELECTRONS- ORBIT THE NUCLEUS, (-)NEGATIVE CHARGE, NO WEIGHT

10. ISOTOPES • ATOMS WITH THE SAME NUMBER OF PROTONS (THEY ARE ALL THE SAME ELEMENT), BUT A DIFFERENT NUMBER OF NEUTRONS • C-12, C-13, C-14 • RADIOACTIVE ISOTOPES- UNSTABLE AND DECAY (BREAK DOWN OVER TIME)

11. C-14 DATING • USED TO DETERMINE THE AGE OF MANY FOSSILS • HALF-LIFE= THE AMOUNT OF TIME IT TAKES HALF OF THE RADIOISOTOPES TO DECAY AWAY- • C14 HALF LIFE IS ABOUT 6000 YEARS

12. GROUPS OF ATOMS • COMPOUND- 2 OR MORE DIFFERENT TYPES OF ATOMS BONDED TOGETHER EXAMPLES • WATER- H20 • CARBON DIOXIDE- CO2 • TABLE SALT- NaCl

13. FORMING BONDS • ATOMS WILL FORM BONDS IN ORDER TO HAVE A FULL OUTER SHELL OF ELECTRONS • ATOMS ARE UNHAPPY IF THEY DON’T HAVE A FULL OUTER ELECTRON SHELL • ATOMS CAN GET A FULL OUTER SHELL BY DONATING,ACCEPTING OR SHARING ELECTRONS

15. BONDS • IONIC BOND- AN ATTRACTION BETWEEN 2 ATOMS CAUSED WHEN ONE ATOM DONATES ELECTRONS TO THE OTHER, THE OPPOSITE CHARGES PRODUCED BY THIS DONATION ATTRACT EACH OTHER • TABLE SALT- NaCl

17. COVALENT BOND • FORMED WHEN ATOMS SHARE ELECTRONS • WATER- H2O • MOLECULE- 2 OR MORE ATOMS JOINED BY COVALENT BONDS

19. IMPORTANT MOLECULES • WATER • POLAR AS A RESULT OF OXYGEN CRAVING THE SHARED ELECTRONS AND GETTING THEM MORE THAN ONE THRID OF THE TIME • HAS 2 POSITIVE ENDS AND NEGATIVE END • HYDROGEN BONDS- WEAK ATTRACTIONS BETWEEN WATER MOLECULES

21. UNIQUE PROPERTIES GOOD BIOLOGICAL SOLVENT FOR POLAR SOLUTE • SOLVENT- WATER • SOLUTES- TEA AND SUGAR • POLARITY CAUSES SOLUTE TO “STICK” TO THE ENDS OF THE WATER MOLECULES

22. COHESIVE • STICKS TO ITSELF AND MIXES WELL WITH OTHER POLAR CHEMICALS • GOOD MEDIUM FOR TRANSPORT • BLOOD IS WATER BASED • PROTEINS, SUGARS AND SALTS ARE DISSOLVED IN THE BLOOD

23. HIGH HEAT CAPACITY • WATER RESISTS TEMPERATURE CHANGE • HEAT= WIGGLING MOLECULES • HYDROGEN BONDS INHIBIT WIGGLING, THEY MUST BE BROKEN FOR THE MOLECULES TO WIGGLE A LOT • COOLING- BONDS REFORM

24. VAPORIZATION • EVAPORATION • USED TO COOL OUR BODY • THE MOLECULES WITH THE GREATEST HEAT (HIGHEST SPEED) ARE THE ONES THAT ESCAPE

26. ICE FLOATS • FROZEN WATER IS LESS DENSE • AS WATER FREEZES, THE MOLECULES ORGANIZE THEMSELVES SO THAT ALL THE POLES ARE ALIGNED • THIS TAKES UP MORE SPACE AND SPREADS THEM OUT

27. ACIDS AND BASES • WATER DISSOCIATES (TEMPORARILY COMES APART) INTO ITS H+ AND OH- COMPONENTS. • ACID- HAS MORE H+ • BASES- MORE OH- IF A BASE IS MIXED WITH AN ACID, THE EXTRA OH- WILL COMBINE WITH H+ TO FORM WATER

29. pH SCALE • MEASURES ACIDITY OR ALKALINITY • 0-14 • 0- ACID= LOTS OF H+ • 14- BASIC= LOTS OF OH- • 7= NEUTRAL

30. CHEMICAL REACTIONS... • ARE FUSSY! • OFTEN REQUIRE A SPECIFIC pH IN ORDER TO OCCUR • BUFFERS HELP MODERATE pH CHANGES IN OUR BODIES

31. ACID RAIN • NORMAL RAINWATER HAS A pH OF 5.6 • SLIGHTLY ACID BECAUSE OF CARBON DIOXIDE DISSOLVED IN IT • DRINKING A SODA QUICKLY CAUSES YOUR MOUTH TO BURN BECAUSE OF THE CARBON DIOXIDE MIXED WITH THE WATER • SOME LAKES IN NORTH-EASTERN U.S. AND CANADA- HAVE pH OF 5.0 AND 4.0

32. CAUSE • AIR POLLUTION • NITROGEN OXIDES + WATER= NITRIC ACID • SULFUR OXIDES + WATER= SULFURIC ACID • PROBLEM IN LAKES WHERE LIMESTONE BEDROCK IS NOT PRESENT

33. SOLUTIONS • LOWER EMISSIONS FORM AUTOS • BURNING LOW SULFUR COAL

34. ORGANIC COMPOUNDS • CONTAIN CARBON AND HYDROGEN • BIOLOGICAL CHEMICALS • CAN BE COMPLEX OR SIMPLE • COMPLEX FORMS ARE OFTEN MERELY REPEATING UNITS • MONOMER- BASIC UNIT • POLYMER- MANY MONOMERS CONNECTED TOGETHER- 4 GROUPS

35. 1. CARBOHYDRATES • STORE ENERGY • MONOMER- MONOSACCHARIDE • EX- GLUCOSE- 6 CARBONS • DISACCHARIDES- 2 HOOKED TOGETHER- SUCROSE- TABLE SUGAR • CONDENSATION SYNTHESIS USED TO CONNECT MONOMERS • Condensation = Dehydration

37. HYDROLYSIS • USED TO TAKE POLYMERS APART • MUST INSERT WATER

39. POLYMERS= POLYSACCHARIDES • GLYCOGEN, STARCH AND CELLULOSE • ALL 3 ARE MADE OF MANY GLUCOSE MOLECULES CONNECTED TOGETHER • CELLULOSE- INDIGESTIBLE (FIBER) • ITS CONNECTIONS ARE NOT AFFECTED BY HUMAN ENZYMES

41. 2. LIPIDS • DO NOT DISSOLVE IN WATER BECAUSE THEY ARE NON-POLAR • GLYCEROL (MONOMER) + 3 FATTY ACIDS (MONOMER) = TRIGLYCERIDE (POLYMER) • FUNCTIONS= ENERGY STORAGE, INSULATION, CUSHION

43. SATURATED VS. UNSAT. • SATURATED FATS- SATURATED WITH HYDROGENS, ANIMAL FATS, SOLID AT ROOM TEMPERATURE, BAD FOR YOU • UNSATURATED- HAS DOUBLE BONDS (NOT AS MANY HYDROGENS), VEGETABLE FATS, LIQUID AT ROOM TEMP, NOT AS BAD

44. SOAPS ARE NOT FATS... • ... BUT THEY ARE IMPORTANT • THEY HAVE A POLAR AND A NON-POLAR END AND ACT LIKE A BRIDGE • THE POLAR END STICKS TO WATER AND THE NON POLAR END STICKS TO FATS • THIS HELPS FATS TO “DISSOLVE” IN WATER

45. PHOSPHOLIPIDS • CELL MEMBRANES ARE COMPOSED OF THESE MOLECULES • HAVE A PHOSPHATE THAT MAKES ONE END WATER SOLUBLE • WHEN PLACED IN WATER, THE NON-POLAR (HYDROPHOBIC) ENDS “HUDDLE” TOGETHER AND FORM A DOUBLE LAYER

46. 3. PROTEINS • MONOMER= AMINO ACIDS -THERE ARE 20 DIFFERENT TYPES • ALL HAVE IDENTICAL “CORES” BUT A DIFFERENT CHEMICAL SIDE CHAIN • PEPTIDE BONDS LINK AMINO ACIDS TOGETHER • HYDROLYSIS- BREAKS THE BOND • CONDENSATION- MAKES IT

47. POLYPEPTIDE • CHAIN OF AMINO ACIDS HOOKED TOGETHER BY PEPTIDE BONDS • DNA HOLDS THE RECIPIE FOR THE ORDER OF THE DIFFERENT AMINO ACIDS IN EACH PROTEIN • THE LINKS OF THE CHAIN INTERACT WITH OTHERS UPSTREAM AND DOWNSTREAM TO CAUSE FOLDING AND COILING (SPIRAL OR SHEET) -THIS IS SECONDARY STRUCTURE

50. FOLDING AND COILING... • THE VARIOUS SHEETS AND COILS INTERACT WITH EACH OTHER TO FORM A MORE COMPLEX FOLDING • THIS IS CALLED TERTIARY STRUCTURE • SHAPE IS VERY IMPORTANT TO SOME PROTEIN’S FUNCTION - EX. ENZYMES ARE THE CELL’S TOOLS